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Title: Nanoscale Visualization of Reversible Redox Pathways in Lithium-Sulfur Battery Using In Situ AFM-SECM
Deducing the electrochemical activity of intermediates and providing materials solution to alter their reaction pathways holds the key for developing advanced energy storage systems such as lithium-sulfur (Li-S) batteries. Herein, we provide mechanistic perspectives of the substrate guided reaction pathways of intermediate polysulfides and their correlation to the redox activity of discharge end products using In Situ atomic force microscopy-based scanning electrochemical microscopy (AFM-SECM) coupled Raman spectroscopy at nanoscale spatiotemporal resolution. In Situ SECM intermediate detection along with Raman analysis at the electrode/electrolyte interface reveals that the precipitation of Li 2 S can occur via an electrochemically active lithium disulfide (Li 2 S 2 ) intermediate step. With a detailed spectro-electrochemical and morphological mapping, we decipher that the substrate-dependent Li 2 S 2 formation adversely affects the Li 2 S oxidation in the subsequent cycles, thereby reducing the round-trip efficiency and overall performance of the cell. The present study provides nanoscale-resolved information regarding the polysulfide reaction pathways in Li-S batteries with respect to the electrode structure and its properties.  more » « less
Award ID(s):
1751472
NSF-PAR ID:
10391934
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Journal of The Electrochemical Society
Volume:
169
Issue:
6
ISSN:
0013-4651
Page Range / eLocation ID:
060501
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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